Plural of Hypothesis | Definition, Spelling & Examples

The plural of “hypothesis” is hypotheses, pronounced [hahy-poth-uh-seez].

“Hypothesis” is a Greek-derived irregular plural noun that follows Greek pluralization rules. Instead of following the common pluralization rules of English, where you simply add “-s” or “-es” to the end of the word, Greek-derived words ending in “-is” are made plural by changing the “-is” to “-es.”

Hypotheses in a sentence examples
The scientist proposed several hypotheses before starting the experiment.

After analyzing the data, the team was able to confirm many of their hypotheses.

Hypothesis vs. hypotheses

A hypothesis is an assumption or explanation based on limited evidence and the starting point for further experimentation. It is a testable statement that predicts a possible outcome or relationship between variables in scientific research.

Hypotheses is the plural word of “hypothesis” and refers to multiple explanations or assumptions that are to be tested in a scientific way.

Hypothesis vs. hypotheses sentence examples
The hypothesis about sunlight and its effects on plant growth turned out to be true.

By comparing different hypotheses, the team aimed to find the most plausible explanation for the phenomenon.

What is an irregular plural noun?

People sometimes mistakenly use “hypothesises” as the plural of “hypothesis,” but that is incorrect. The word “hypothesis” is an irregular plural noun, meaning it doesn’t follow the regular rules of pluralizing by simply adding “-s” or “-es” to the end of the noun (e.g., dog/dogs or wish/wishes).

Instead, “hypothesis” follows Greek pluralization rules and changes the “-is” at the end of the singular form to “-es” to form the plural (e.g., diagnosis/diagnoses or crisis/crises).

“Hypothesis” happens to be a Greek-derived irregular plural, but there are irregular plurals that are derived from other languages such as Latin (e.g., stimulus/stimuli), Old English (e.g., man/men), and Dutch (e.g., hoof/hooves).

Irregular plurals examples
Singular Plural
matrix matrices
woman women
parenthesis parentheses
vertex vertices

Another type of irregular plural is called zero plurals. This is a noun that remains the same in both the singular and plural forms.

Zero plurals examples
Singular Plural
spacecraft spacecraft
jeans jeans
furniture furniture
species species

Frequently asked questions about the plural of hypothesis

Is “hypothesis” a word?

Yes, hypothesis is a word. It refers to an assumption or explanation based on limited evidence and is the starting point for further experimentation.

The plural of hypothesis is hypotheses.

Scribbr’s free Grammar Checker can help ensure all your words are correct no matter what you’re writing.

What is a synonym for “hypothesis”?

Some synonyms for the word “hypothesis” include:

  • Premise
  • Presumption
  • Assumption
  • Supposition
  • Theory

Scribbr’s free Paraphrasing Tool will help you easily find synonyms for any word you use in your writing.

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Cove, R. (2024, October 03). Plural of Hypothesis | Definition, Spelling & Examples. Scribbr. Retrieved December 3, 2024, from https://www.scribbr.com/plurals/hypothesis-plural/

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Ryan Cove

Ryan has an academic background in psychology, focusing on industrial/organizational psychology and neuroscience. Despite this focus, he has been a content writer and editor for five years. His favorite thing about this career is researching and writing about a wide variety of topics.